An organic electroluminescence (EL) display device (referred to herein as an EL display device) has a plurality of pixels formed on a substrate. In addition, each of the plurality of pixels includes a plurality of transistors, a capacitor element, and an organic light emitting element (referred to herein as a light emitting element). The light emitting element is formed from, for example, an anode, a cathode and an EL layer. For example, carriers (electrons, holes) are injected into the EL layer from the anode and the cathode due to a potential difference applied to the anode and the cathode, and carrier recombination occurs in the EL layer. Then, the organic compound included in the EL layer is in an excited state. Furthermore, energy is released when this excited state relaxes to a ground state, whereby the light emitting element emits light. Each pixel is driven by a signal controlling a pixel. By controlling the driving of the transistor included in each pixel by this signal, the current supplied to the light emitting element is controlled. Then, the EL display device can display images. In recent years, there has been increasing demand for displaying images finely on display devices. That is, the demand for higher definition of EL display devices is increasing. When a display device becomes high definition, the amount of data of the image also increases and power consumption increases. Therefore, in an EL display device, there is also a high demand for low power consumption.
As the definition of the EL display device becomes higher, the distance between pixels becomes closer. Therefore, the influence of a leak current (also referred to herein as “lateral leak current”) flowing between adjacent pixels becomes significant. In addition, in order to reduce the power consumption of an EL display device, it is possible to reduce the difference between the voltages applied between the anode and the cathode by using a material having a high conductivity for the EL layer. However, since a material with high conductivity has high mobility, the lateral leak current is also large. In the EL display device, the lateral leak current causes adjacent pixels to emit light, and there is a possibility of reducing color purity. For example, Japanese Laid Open Patent Publication No. 2016-85913 discloses an EL display device in which a lateral leak current is reduced.